Diamond whetstone



FIG. 1 is front elevational view thereof of a diamond whetstone showing my new design where the whetstone is placed on the base;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a perspective view thereof;

FIG. 8 is another perspective view thereof; and,

FIG. 9 is a perspective view there of a diamond whetstone showing my new design where the whetstone is separated from the base.

The broken lines illustrate portions of the environment structure which forms no part of the claimed design. 

CLAIM The ornamental design for a diamond whetstone, as shown and described. 